All Katy Perry wants is the spotlight, and she’ll follow the path of others to get there, raising eyebrows à la Alanis, strutting like Gwen Stefani, and relying on Britney’s hitmaker Max Martin for her hooks. She never breaks away from the expected lite club beats that transition from day to night without a hitch or the chilly, stainless steel ballads designed to lose none of their luster on repeat plays. Perry acknowledges some trends -- she salutes KeSha on “Last Friday Night (T.G.I.F.),” replicates Ryan Tedder’s glassy robotic alienation on “E.T.,” but tellingly avoids ripping off Lady Gaga. Perry is at her best when she’s delivering sleek singles like “Teenage Dream” and “Hummingbird Heartbeat” with efficiency.